As mobile Internet access has become a main characteristic of a terminal, a technical solution used by the terminal to access a network continuously develops. This greatly improves an information obtaining rate of a terminal product. Transmission Control Protocol/Internet Protocol (TCP/IP) commonly used in the mobile communications field is a connection-oriented, reliable, and byte stream-based transport layer communication protocol.
In a process in which a terminal accesses a network by using the TCP/IP protocol, a packet is frequently discarded (which is also referred to as a packet loss). A current processing method is usually that a transmit end retransmits data. In the current processing method, whether a packet is lost is determined depending on a feedback from a receive end. For example, if the transmit end has not received, within a specified time period, a feedback message such as an ACK sent by the receive end, it is determined that a packet is lost, and a packet including data of the lost packet is resent. In this solution, a terminal has a relatively large delay when responding to a packet loss, a stalling time of data transmission between the terminal and a network device is relatively long, and real-time communication quality is relatively severely affected.